I heard some ups and downs about that clutch and its corresponding flywheel. I highly recommend the ram he clutch. It's 199 at american muscle. I also recommend getting the ram billet steel flywheel. That's gonna run you 299 which is more than you pay for the clutch but it'll ensure maximum grip.
I had the same problem as you a few months ago. Engine would roar but acceleration was stalled and reduced. Finally I decided if this clutch was gonna give out better close to home than anywhere else so I gave it a nice burnout and sure enough it called it a life.
I did my research and figured this clutch setup was best for me. My car is mostly stock. With my old clutch I would get a lot of 'chatter' when accelerating from ist gear or reversing. I had to rev up quite a bit to avoid the whole car shaking and rumbling at take off.
Cutting to the point I had this clutch installed right before thanksgiving and I've already broke it in with 1,500 miles. Usually it takes 500-1000 miles of city or city/highway driving of normal driving to break in a new clutch. No burning out no fast driving, just nice and casual.
I couldnt be happier there is absolutely no chatter I can accelerate to 1 mile per hour with no shaking at all. I highly recommend it man I think youll love it.
Tip for those who do purchase.. the ram hdx clutch comes with a throw out bearing but it didn't fit on my car.. I bought a ford performance throw out bearing as well as a roller pilot bearing, both are mandatory replacements as they will prolonge the life of your clutch and flywheel.
If you don't wish to spend so much on a new flywheel and looking for a cheap fix make sure your flywheel is in good condition even after it gets resurfaced. Resurface your current flywheel if you re use or kiss your new clutch goodbye.
Good communication with your mechanic is VITAL. if you tackle the labor yourself make sure you do your research. If you hire a mechanic let him know you know what your doing as they won't guarantee their work if you buy aftermarket parts remember that.
I apologize for the long post but if you read this far I hope this will save you money and time in the long run. I've owned my car for 3 years and had to swith the clutch twice. I learned the hard way the 1st time for trying to be cheap.
One more thing.. if you do buy a flywheel.. the 4.6 can either have a 6 bolt or 8 bolt. The best way to know which set up your car has is to find out if you have a Windsor or Romeo engine. One has 11 valve cover bolts the other has 13 or more I'm not sure. Do your research on this aswell and know one thing.. DO NOT TRUST THE VIN NUMBER to tell you what flywheel or engine you have. Ford lied to me and caused me to order the wrong flywheel. Even ford has a hard time telling you what flywheel you have.
Good luck to all who are replacing their clutch. Do it right or don't do it at all.